Miami Beach is a city in Miami-Dade County, Florida, United States, incorporated on March 26, 1915. The municipality is located on a barrier island between the Atlantic Ocean and Biscayne Bay, the latter which separates the Beach from Miami city proper. The neighborhood of South Beach, comprising of the southernmost 2.5 square miles (6.5 km2) of Miami Beach, along with Downtown Miami and the port collectively form the commercial center of South Florida. As of the 2000 census, the city had a total population of 87,933. 55.5% of the population was foreign born. A 2009 population estimate for the city was 88,065. Miami Beach has been one of America's pre-eminent beach resorts since the early 20th century.